The present invention relates in general to manually operated imprinting machines, and more particularly to manually operated imprinters of the type using a plurality of printing wheels each of which may be selectively indexed so as to be able to present a variety of indicia to a document, usually formed of one or more sheets, placed on an imprinting bed over the printing wheels.
Imprinting machines wherein a plurality of printing wheels may be manually indexed to present a variety of indicia to a sheet or plural sheet document or sales ticket, concurrently with imprinting on the document or sales ticket certain information embossed on a credit card or the like, have come into wide use for recording sales information in the petroleum industry, for example at gasoline service stations, and to some extent in the bank sponsored credit industry. Such imprinting machines, which are frequently referred to as imprinters, have been utilized to transfer embossed information from a plastic card as well as data relating to the particular sales transaction, such as date, price, etc., on a document usually formed of a plurality of sheets forming a sales ticket, so that one of the sheets of the plural sheet document may be subsequently relied upon as the record of the transaction and processed for purposes of billing the customer. The documents that are commonly used to record such transactions usually consist of a plurality of sheets containing one or more carbons to provide several copies of the transaction. Use of a rolling platen has been resorted to for carrying out the printing operation by pressing the plural document sheet positioned on an imprinting bed against the printing wheels and the credit card to obtain clear impressions on each copy. An example of such a variable data imprinting machine is disclosed in my earlier U.S. Pat. No. 3,739,716 granted June 19, 1973.
In order to make variable data imprinting machines attractive to a wider variety of users, and thus achieve a considerably larger volume use of such devices, it is important to reduce the cost of production, without however reducing their mechanical effectiveness. Presently available variable amount imprinters wherein the printing wheels are driven by mechanical means carry a heavy cost penalty because of the steel rack system used to position the printing wheels. The construction in current use depends on precisely made steel racks, usually of stainless steel, which are held in precise proximity to the toothed portion of the print wheels by stampings, dye castings, steel shafts and the like. The racks are, of course, held in close proximity where they run under the closely spaced print wheels in driving relation to the toothed portion of the print wheels, but must be arranged in such a way to provide sufficient lateral spacing between the racks along a keyboard or control panel where an operator may grasp them without interference from the next adjacent rack terminus, usually a manipulating knob. Presently, this lateral spacing or "offsetting" of the racks in the keyboard or control panel zone relies on creating offset arms on the individual racks, which is quite expensive because of the extra forming operation and the metal scrap generated, or the spacing or offsetting may involve separate offsetting arms which may be attached to each rack by spot-welding or other mechanical means, either of which adds substantially to the cost of the item. Regardless of the means used to obtain this "offsetting" of the rack manipulated portions in the keyboard zone, a guidance and support system must be present to have the racks run smoothly, which usually takes the form of plastic molded blocks, wheels, runners and the like all of which add complexity and cost to the unit.
An object of the present invention therefore, is the provision of a novel variable data imprinting machine having a plurality of numbered amount wheels which are closely packed together and mechanically driven by a novel rack structure in a manner which permits drastic cost reduction and greatly simplifies the mechanism while retaining the dependability of earlier variable data imprinting machines and requires less space.
Another object of the present invention is the provisiion of a novel variable data imprinting machine involving a plurality of closely spaced or packed print wheels projecting through an imprinter bedplate for imprinting number or character information on plural sheet documents such as sales tickets or the like supported on the bed, along with imprinting credit card information thereon, wherein the print wheels are indexed to manually adjusted positions by molded plastic racks adjustable from a keyboard or control panel area and moving along serpentine paths through the print wheel zone.
Another object of the present invention is the provision of a novel variable data imprinting machine having a plurality of character bearing print wheels which are closely packed together and mechanically driven by a novel rack structure to position selected characters in upwardly facing printing position, and wherein a novel mechanism is provided to automatically accurately center the upwardly facing characters in the predetermined position during movement of a printing roller carriage from normal parked position through an imprinting stroke.
Yet another object of the present invention is the provision of a novel variable data imprinting machine as described in any of the three preceding paragraphs, wherein there is provided a novel interlock mechanism designed to maintain the printing roller carrier locked in parked position at the end of its return stroke after imprinting, until at least one of the racks for positioning the imprinting wheels has been readjusted, so that the carrier cannot be reciprocated through another printing stroke without readjustment of the racks.
Other objects, advantages and capabilities of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings illustrating a preferred embodiment of the invention.